Acetyl-L-Carnitine and Brain Health

Today you get another excerpt from Lyme Brain, which by the way is getting close to being released! Although these excerpts talk about Lyme Brain, the nutrient acetyl-L-carnitine can be helpful for many people, so if you don’t have Lyme disease, still have a read! It’s good for protecting the brain from aging and oxidative stress, and boosting the brain’s metabolism. The book Lyme Brain will be available through www.lymebrainbook.com for purchase in another week or two. Woohoo!!

Acetyl-L-Carnitine and Brain Health

Acetyl-L-carnitine was mentioned briefly in the section on acetylcholine support as a possible donor of the acetyl group required to make that particular neurotransmitter.

Even outside of that role, acetyl-L-carnitine has long been used for brain and cognitive support, and there is much research supporting its use and benefit. It is way more absorbable than regular L-carnitine, and the acetyl-L form has superior blood-brain barrier penetration, which is desirable for those needing help with Lyme Brain.

There are several mechanisms by which acetyl-L-carnitine helps the brain. It is a nutrient that helps to produce energy, thus fueling the cells, boosting their metabolism and making them function better. It does this by reducing glucose metabolism to lactate.[i] It also helps to metabolize fat and cholesterol so that the brain does not get clogged with plaques and deposits.

Acetyl-L-carnitine can help to prevent the buildup of amyloid plaque, which can contribute to cognitive decline. It does this by promoting the production in nerve cells of alpha-secretase instead of beta-secretase, resulting in less beta amyloid plaque. It boosts levels of brain-derived neurotrophic factor (BDNF), which helps to repair damaged cells and even produce new brain cells.

Acetyl-L-carnitine boosts nerve transmission. One study showed that diabetic neuropathy was helped significantly by consistent daily dosing.[ii] Patients reported less neuropathic pain, improvement in nerve conduction and some nerve regeneration.

It helps to repair myelin sheaths (as we discussed, B12 can too). While mechanisms are not fully understood, research points to a regulation of the myelin basic protein (MBP) gene, which modulates the turnover of myelin basic protein, thus stabilizing and maintaining membrane integrity.[iii]

It also helps to repair any damage to the blood-brain barrier caused by alcohol and other toxins, inflammation etc. It does this by boosting the antioxidant enzymes that naturally protect the blood-brain barrier from toxic stress. Because we know that inflammatory damage to the blood-brain barrier can contribute to cognitive issues, neurological degeneration, reduced learning, memory decline and depression, acetyl-L-carnitine can help to offset such damage and, for this reason alone, is an important nutrient.

As an overall antioxidant, acetyl-L-carnitine is highly neuroprotective, boosting glutathione levels in the brain.

In terms of neurotransmitters, we saw that acetyl-L-carnitine supports acetylcholine. It also has been found to support dopamine levels. Research shows that there is a decline in dopaminergic receptors with age, but that administration of acetyl-L-carnitine for a 3-month period diminished the reduction in binding.[iv]

Another study showed that acetyl-L-carnitine increased norepinephrine in the hippocampus and serotonin in the cortex.[v] Supporting norepinephrine and serotonin in the brain can help with depressive symptoms as well as cognitive deficits. This study also confirmed acetyl-L-carnitine’s ability to boost brain cell metabolism and energy.

As you can see, acetyl-L-carnitine may be one of the most important nutrients for the brain. It boosts metabolism, acts as a neuroprotectant, helps the integrity of both the blood-brain barrier and the myelin sheaths around nerves and perhaps, most importantly, has the ability to repair already damaged nerve cells and structures, and promote the creation of new, healthy ones.

From a clinical standpoint, it has the ability to boost working memory and retrieval, relieve depression and enhance overall mood, boost concentration and increase mental energy—all things that would be of benefit in Lyme Brain. It is worth trying for 3–6 months, as improvements do not necessarily happen overnight with this nutrient.

[i] Smeland, O B, T W Meisingset, K Borges, and U Sonnewald. “Chronic acetyl-L-carnitine alters brain energy metabolism and increases noradrenaline and serotonin content in healthy mice.” Neurochem Int 61, no. 1 (July 2012): 100-7.

[ii] Evans, J D, T F Jacobs, and E W Evans. “Role of acetyl-L-carnitine in the treatment of diabetic peripheral neuropathy.” Ann Pharmacother 42, no. 11 (November 2008): 1686-91.

[iii] Traina, G, G Federighi, M Macchi, R Bernardi, M Durante, and M Brunelle. “Modulation of Myelin Basic Protein Gene Expression by Acetyl-l-Carnitine.” Mol Neurobiol 44, no. 1 (August 2011): 1-6.

[iv] Sershen, H, Jr., L G Harsing, M Banay-Schwartz, A Hashim, M T Ramacci, and A Lajtha. “Effect of acetyl-L-carnitine on the dopaminergic system in aging brain.” J Neurosci Res 30, no. 3 (November 1991): 555-9.

[v] Smeland, O B, T W Meisingset, K Borges, and U Sonnewald. “Chronic acetyl-L-carnitine alters brain energy metabolism and increases noradrenaline and serotonin content in healthy mice.” Neurochem Int 61, no. 1 (July 2012): 100-7.